Kepler-33

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Kepler-33

Observation data Epoch J2000      Equinox J2000
Constellation	Lyra
Right ascension	19h 16m 18.61s[1]
Declination	+46° 00′ 18.8″[1]
Apparent magnitude (V)	13.988
Characteristics
Spectral type	G1IV
Astrometry
Proper motion (μ)	RA: –0.39[1] mas/yr Dec.: -14.96[1] mas/yr
Details
Mass	1.164 [2] M☉
Radius	1.615 [2] R☉
Temperature	5849 [2] K
Metallicity [Fe/H]	0.12 [2] dex
Age	4.27 ± 0.87 [3] Gyr
Other designations
KOI-707, KIC 9458613, 2MASS 19161861+4600187[4]
Database references
SIMBAD	data

Kepler-33 is a star in the constellation of Lyra with a system of five known planets. Having begun to evolve from the main sequence^[3], it has roughly 161.5% of the Sun's radius but only 116.4% of the Sun's mass. Given its mass and temperature, it is likely an early G-type star. The star's distance is not known.

Planetary system

On January 26, 2012, a system of five planets around the star was announced^[3]. However, unlike other planets confirmed via Kepler, their masses are not known, as Doppler Spectroscopy measurements were not done before announcement. Judging by their radii, b may be a large Super-Earth or small Hot Neptune while the other four are all likely to be the latter.
Planets b and c may actually be in a 7:3 resonance, as there is a 0.05 day discrepancy; there is also a small 0.18 day discrepancy between a 5:3 resonance between planets c and d. The other planets do not seem to be in any resonances, though near resonances are 3d:2e and 4e:3f.

The Kepler-33 system^[3]

Companion (in order from star)	Mass	Semimajor axis (AU)	Orbital period (days)	Eccentricity	Radius
b	—	0.06544	5.667939	—	1.504 R⊕
c	—	0.11484	13.17563	—	2.751 R⊕
d	—	0.16053	21.7759	—	4.564 R⊕
e	—	0.20656	31.78438	—	3.446 R⊕
f	—	0.2449	41.02903	—	3.827 R⊕